London (CNN)Britain's exit from the European Union moved another step closer Thursday after the legislation enabling the country's departure was given royal assent by Queen Elizabeth II.

The Queen's signature means that British Prime Minister Theresa May is now able to move forward and trigger Article 50, allowing formal talks to begin between Downing Street and the EU's 27 member states on the terms of the divorce.

The negotiations are expected to take up to two years once May finally invokes the leaving mechanism later this month.

What is royal assent?

The news of the royal assent was announced in the House of Commons by the Speaker of the House.